Substituted bicyclic 1-halogeno-1-cyclopropanecarboxylates have been prepar
ed by elimination of molecular nitrogen from Chalogeno-7-aryl-1-methyl-2,3,
7-tniazabicylo[3.3.0]oct-2-en-4-carboxylates, which were obtained by the re
action of 7-aryl-1-methyl-2,3,7-triazabicyclo[3.3.0]oct-3-encarboxylates wi
th halogens (Cl-2, Br-2).